College of Grassland Agriculture, Northwest A&F University, Yangling, China.
Department of Biology and Microbiology, South Dakota State University, Brookings, SD, USA.
Plant Biol (Stuttg). 2022 Mar;24(2):323-332. doi: 10.1111/plb.13369. Epub 2021 Dec 6.
Symbiotic nitrogen fixation in legumes is an important source of nitrogen supply in sustainable agriculture. Salinity is a key abiotic stress that negatively affects host plant growth, rhizobium-legume symbiosis and nitrogen fixation. This work investigates how the symbiotic relationship impacts plant response to salinity stress. We assayed the physiological changes and the proteome profile of alfalfa plants with active nodules (NA), inactive nodules (NI) or without nodules (NN) when plants were subjected to salinity stress. Our data suggest that NA plants respond to salinity stress through some unique signalling regulations. NA plants showed upregulation of proteins related to cell wall remodelling and reactive oxygen species scavenging, and downregulation of proteins involved in protein synthesis and degradation. The data also show that NA plants, together with NI plants, upregulated proteins involved in photosynthesis, carbon fixation and respiration, anion transport and plant defence against pathogens. The study suggests that the symbiotic relationship gave the host plant a better capacity to adjust key processes, probably to more efficiently use energy and resources, deal with oxidative stress, and maintain ion homeostasis and health during salinity stress.
豆科植物的共生固氮是可持续农业中氮素供应的重要来源。盐度是一种关键的非生物胁迫因素，会对宿主植物的生长、根瘤菌-豆科植物共生体和固氮作用产生负面影响。本研究探讨了共生关系如何影响植物对盐胁迫的响应。我们检测了在盐胁迫下具有活性根瘤（NA）、非活性根瘤（NI）或无根瘤（NN）的紫花苜蓿植物的生理变化和蛋白质组谱。我们的数据表明，NA 植物通过一些独特的信号调控来响应盐胁迫。NA 植物表现出与细胞壁重塑和活性氧清除相关的蛋白质上调，以及与蛋白质合成和降解相关的蛋白质下调。数据还表明，NA 植物与 NI 植物一起，上调了与光合作用、碳固定和呼吸作用、阴离子转运以及植物对病原体防御相关的蛋白质。该研究表明，共生关系赋予宿主植物更好的能力来调整关键过程，可能更有效地利用能量和资源，应对氧化应激，以及在盐胁迫下维持离子平衡和健康。
